What is a Satellite phone?

What is a satellite phone? Why are they used and why would I need one?

A satellite phone, quite simply, is a mobile phone handset which has satellite capabilities built in to send and receive phone calls via satellites orbiting the earth. If the bit about satellites orbiting the Earth doesn’t make sense at this stage, might I suggest you nip off to Google and do a little research? I’ll wait for you here.

For those of you that already know about the above, you’ll also appreciate that your standard mobile phone signal and the cell towers that provide that signal, do not cover everywhere on the planet. Everyone has had those phone waving moments in the attempt to gain one bar of signal so you can call or text I’m sure.

If you’re traveling somewhere remote like the middle of the Sahara desert or the summit of Mount Everest (good luck to you first of all and well done) then I’m sure you won’t be surprised to find that there’s no mobile coverage there. This is where the humble satellite phone comes in, all you need is a clear line of sight to the sky and you can make your call.

Take out your satellite phone, point the antenna to the sky and you call shoots off to a satellite orbiting the earth 500 or so miles up, traveling at 17,000 miles per hour and back down to a ground station where your call is routed to the number you’ve dialed.

Your typical satellite in the Iridium constellation (that’s a network of orbiting satellites that are used by the Iridium brand of satellite phones, not a constellation of stars!) sends down 48 coverage beams and each beam covers a diameter of 250 miles meaning each satellite’s 48 overlapping beams cover a diameter of 2800 miles. The Iridium network has 66 satellites in a polar orbit (that means they go from South to North in a clockwise direction around the planet) so as you can imagine, that’s one heck of an area covered.

The Inmarsat system works slightly differently and consists of just 3 geostationary satellites (that means they stay in the same position over the same point on the planet) at a higher orbit so they have greater ground coverage. These satellites provide an almost global level of coverage, one covering the Americas, one covering Europe, Africa and the Middle East and one covering Australasia.

Constellation of 66 satellites in a near circular polar orbit moving at a speed of 16,800mph

7 spare satellites in a lower storage orbit in case any satellites fail.

The only handheld satellite voice solution that works at both poles.

Main form of satellite voice comms used by US and UK militaries.

Strong product portfolio of devices and accessories now including the ability to create a wireless access point and also allow GPS tracking for security & Safety purposes (Iridium extreme handset only).

2 thoughts on “What is a Satellite phone?”

Thanks for helping me learn more about satellite phones. I didn’t know that you just need to be able to see the sky to make sure the phone works correctly. This seems extremely useful especially if you like to go camping a lot.

My husband and I are going on a safari trip together, and I think that you’re right that getting a satellite phone to rent for the trip will be a good idea. As you said, there may not be much mobile coverage there, and we’ll want to keep in contact with our camp and with each other, so the fact that all it needs is open sky is a major benefit to that. I appreciate you breaking down the differences in satellite phone types, though it’s still hard to decide between the ruggedized, water-resistance of the Inmarsat and the large coverage fo the Iridium phones.